1. Field of the Invention
The present invention generally relates to a method of, and apparatus for, making a thermally-insulating insulation for installation in the field and, more particularly, relates to a method of, and apparatus for, installing the thermally-insulating insulation and, yet more particularly, relates to the installed insulation itself which has novel thermally-insulating, non-flammable, venting and structural characteristics.
2. Description of the Prior Art
In order to conserve energy in residential, industrial or commercial buildings, many types of thermally-insulating materials and installation techniques have been proposed heretofore. However, the known materials and their installation have not proven altogether satisfactory.
For example, for retrofitting sidewalls, cellulose, mineral wool, or fiberglass have been blown into the closed cavity formed between the exterior and interior walls of a house by so-called "loose fill blown" techniques. These materials tend to settle due to gravity and pack down in time in the cavity, thereby leaving voids, through which heat can escape. Also, the particulate nature of these loose materials irritates the eyes, lungs and skin of the installer and generally requires him to wear a protective mask, gloves and goggles. Cellulose insulations also represent a fire hazard.
Fiberglass and mineral wool batting, as well as rigid boards have been used, but their installation requires extensive modification to the existing house structure, including, but not limited to, tearing down the walls of the house.
The so-called "foam-in-place" installation techniques introduce a composite stream of partially reacted monomers, e.g. urea and formaldehyde, into the closed cavity, whereupon the reaction is completed in the closed cavity. The urea-formaldehyde foam, however, does not necessarily fill the entire closed cavity during installation, and subsequently shrinks in the closed cavity and eventually deteriorates over time, thereby forming voids through which heat can escape. More importantly, the foam releases offensive-smelling gases which irritate one's mucous membranes and can cause such medical problems as headache, vomiting, and upper respiratory problems. Hence, occupants are eventually forced to leave their homes. In the event of fire, the urea-formaldehyde foam emits a toxic gas.
Another type of insulation material is expanded polystyrene bead insulation. The individual beads are freely blown into the closed cavity. However, the entire closed cavity is not necessarily filled by the loose beads, and the beads do not adequately present a fire barrier. Moreover, the blown-in beads shift and are subject to some settling within the closed cavity. In the event that electrical, plumbing or carpentry maintenance or like repairs are performed near a wall bounding a closed cavity in which the loose blown-in beads have previously been introduced, the beads roll out and empty from the closed cavity when the wall is removed. This "fall-out" problem is highly undesirable.